Hi i am doing a high school research project. Last year we worked on determining what affect certain lighting had on the migration of organisms. We determined which light sources were most damaging and which would be most easily filtered. This year we are trying to work on a solution, i am having trouble coming up with a budget... is their a way to coat glass to filter out certain wavelengths? I have done a lot of research with little success, and i always seem to end up with an article about electron guns to apply thin film layers to the material. Any suggestions as to what i can do for this? i am truly stuck...
Thanks

Hi, what I'm going to do is give you some filter types to help in your search. That way you'll do the research which will help you understand more of the area around your specific request.

 

Notch filter

Band pass filter

Band stop filter

Edge pass filter

Long pass filter

Short pass filter

Dichroic filter

Line filter

 

Searching these should give you and understanding of what's feasible at what cost and the methods of manufacture.

Applying thin films is a standard way to make optical coatings for filtering and antireflection. I don't know if you're going to get away from that.

I don't understand the question.

 

Is this about money or modern ways to create filters?

 

Before modern coatings on glass, filters were made by dissolving suitable absobers in gelatin and letting them set.

This was much cheaper for amateurs.

 

Perhaps you could reasearch this.

 

What light do you want to filter out?

 

https://www.google.co.uk/search?hl=en-GB&source=hp&biw=&bih=&q=gel+filters&gbv=2&oq=gel+filters&gs_l=heirloom-hp.1.0.0l6j0i22i30l4.844.4032.0.12282.11.11.0.0.0.0.235.1502.0j10j1.11.0....0...1ac.1.34.heirloom-hp..0.11.1502.Rr4PoIZwVVc

Thanks guys sorry i was not more specific

I am trying to build a filter for a low pressure sodium bulb, i do not want to just purchase something from a manufacturer. Last year we were able to determine the lengths of certain organisms migrations and how different sources of light pollution effected them, this year the goal is to come up with a solution.

Sodium bulbs produce monochromatic light.

 

(Do you understand this ?)

 

Actually I think they have two very closely spaced lines.

Edited October 15, 201510 yr by studiot

Sodium bulbs produce monochromatic light.

 

(Do you understand this ?)

 

 

Actually I think they have two very closely spaced lines.

 

Yes absolutely I understand, I just don't know where to begin to create a filter. I have spent a lot of time researching it but always return to square one

Sodium bulbs produce monochromatic light.

 

(Do you understand this ?)

 

 

Actually I think they have two very closely spaced lines.

 

Yes absolutely I understand, I just don't know where to begin to create a filter. I have spent a lot of time researching it but always return to square one

 

Yes absolutely I understand, I just don't know where to begin to create a filter. I have spent a lot of time researching it but always return to square one

 

 

 

Are you sure?

 

Look at the 'spectrum' of the low pressure sodium lamp here and compare with other lamps.

 

http://www.lamptech.co.uk/Documents/SO%20Spectral.htm

 

 

If you filter that line out you will have nothing left.

Edited October 15, 201510 yr by studiot

Applying thin films is a standard way to make optical coatings for filtering and antireflection. I don't know if you're going to get away from that.

https://en.wikipedia.org/wiki/Neodymium

and two or three amusing coincidences.

(Well, I think it's amusing, others would probably say serendipitous)

Edited October 15, 201510 yr by John Cuthber

Woops... i meant High Pressure Sodium, what could i do for that?